Improvement in treadles for sewing-machines



N-PETERS. PHOTOJJTHOGRAFHEH. WASHINGTON, D C4 Unrrnn raras PATENTOFFICE.

FRANCIS E. MILLS, 0F SAN FRANCISCO, CALIFORNIA.

IMPROVEMENT IN TREADLES FOR SEWING-MACHINES.

Specification forming part of Letters Patent No. 112,162, dated February2S, 1871.

Be it known that I, FRANCIS E. MILLS, of the city and county of SanFrancisco, in the State of California, have invented an Improvement inSewing-Machine Treadles; and I do hereby declare that the following isafull and exact description thereof, reference being had to theaccompanying drawing, and to the letters of reference marked thereon.

In the accompanying drawing, B represents the bottom or foot-board ofthe treadle; P, the journals orpivots of the treadle; C, the largerpendulous rod, on which the forward part of the foot-boardis hinged; W,the freelyswinging wire rod, supporting the back part of the foot-board;L, the ledge part of the heel-stop; g, the guide-rod of the heel-stop;S, the spring-clasp, holding the rod toits place; a, the workin g arm ofthe treadle, and b the balance-sprin g.

The nature of my invention consists in so lconstructing the footboardand other parts of the treadle, relative to its axis, that the ankle-joint of the operator may always be placed in line with the center ofmotionof the treadle, and held there, thereby saving that unnecessaryexertion and waste of power occasioned by the motion of the entire lowerlimbs whenever the ankle is in any other posi tion.

To effect this object perfectly, three things are requisite in thetreadle, to wit:

First, the treadle must be pivoted at the sides instead of under thebottom of the foot. Thishas already been done. But, owing to the varyingheights of ankles, and more especially to the different heights ofshoe-heels, a fixed and rigid foot-board will not answer the purpose Iaim at. It might be right for one foot and one shoe-heel, but would beentirely wrong for another. Hence,

Second, I make the foot-board, particularly the heel portion, adjustablevertically, so that the ankle may always be brought quickly to thecenter of motion whether the heel worn be high or low. In atreadle ofthis character the foot is inclined to slip from its position. If thetreadle is hung well forward in the frame of the machine, the foot tendsto slip backward. If the treadle han gs toward the back part of themachine, (nearer the operator,) the foot will slip forward 5 and itbecomes necessary to place a ledge or stop, either just back or justforward of the heel, -to secure it in its place. A fixed heel-stop doesnot effect the object; for, while some shoe-heels (like slippers) arebroad, and set under the true heel of the foot, others Vare small, andstand forward toward the center of the foot; and in order to preservethe proper position ot' the ankle with all the various styles and sizesof shoe-heels, l make,

Third, a movable heel-stop, capable of being set quickly at any pointdesired.

That portion of the treadle forward of the axis, including the workingarm, usually preponderates considerably in weight over the back portion,and when the ankle is in the center of motion this preponderance throwsan undue proportion of work upon the heel.

This disproportion is greatly increased when the shoe worn has a smallfashionable heel.

In order to correct this inequality without increasingtheweight andinertia of the treadle, I attach a balancin g-sprin g to some convenientportion of the frame of the machine, connecting the other end of thespring with the treadle in such a manner as to act against the superiorweight of the forward part and assist the heel to that extent.

' Construction.

To secure lightness and ease of adjustment, I generally construct mytreadle in the following manner: I suspend the bottom or footboard ofthe treadle on two pendulous crankformed rods, shaped and coupledtogether in the manner shown in Fig. 1 in the accompanying drawing. Thelarger ofthese two crank-shaped rods may be made of cast-iron. Theprojecting ends form the journals or pivots of the treadle, and are hungin boxes or bearings in the frame of the sewing-machine, about six andone-half inches from the iioor. The working arm of the treadle is alsoattached to some portion of this larger rod.

The smaller rod is made of a large strong wire, bent around theprojecting journals of the larger one close to the sides, so as to swingfreely and independently on the same center.

The forward end of the foot-board is hinged to the bottom or horizontalpart of the large rod, while the back end or heel portion rests VerticalAdjustment. By lifting the heel end of the foot-board and swinging thewire rod backward or forward, it is quickly adj usted vertically, andthe anklebrought opposite the center of motion with any height of heelused, as shown in Fig. 2 of the accompanying drawing.

Adjustable Heel-Stop.

To prevent the foot from' slipping back when properly adjusted, I make a'metal heelstop in the form of a T, as shown in Fig. 3 in theaccompanyin g drawing.

p At right angles to the ledge part L, which rests against the back ofthe heel, a guiderod, g, extends forward on the foot-board six or eightinches. This guide-rod slides in a long spring-clasp fastenedlongitudinally in the center of the foot-board, the tension of thespring being made sufficiently strong to hold the rod by its frictionwherever the ledge may be placed; or, if preferred, the guide-rod may beheld by a set-screw.

The balance-spring may be made of rubber or coiled wire, and may beattached to such part of the frame and the treadle, respectively, asshall be found most convenient in the particular machine used. It shouldbe so attached as to act only against the last half of the downstroke ofthe .forward part of the treadle, and impart the force of its tension infavor of the heel on the return-stroke.

Claims.

What I claim as' my invention, and desire to secure by Letters Patent,is-

1. In combination with a sewing-machine treadle, pivoted at the sides,making that portion of the foot-board on which the heel rests adjustableto different heights relative to the pivot.

2. In combination with a sewing -machine treadle, pivoted at the sides,a foot-board with its forward part hinged to the oscillating frame andits back part resting on a pendulous rod or some other movable support,capa-k ble of being raised or lowered with reference to the axis of thetreadle, substantially as and for the purpose described. j

3. In a sewing-machine treadlc, pivoted at the sides, the slidingheel-stop, substantially as described, or any other equivalent devicefor holding a movable ledge against the heel.

FRANCIS E. MILLS.

Witnesses ASA HoDGE, GEORGE BEIM.

